Uber has previously come under fire for hiring former criminals. In November its parent company was fined $8.9 million (£6.4 million) by authorities in Colorado for hiring 60 drivers with convictions which banned them for working for rideshare companies under Colorado state law.

At the time, Uber attributed the breach to a "process area" inconsistent with the state's regulations and said all drivers must undergo a third-party background screening.

Uber has declined to comment on reports of Mr Vasquez's conviction and the company's hiring policies while the current police investigation continues.

Uber immediately suspended all testing of its self-driving fleet in cities across North America following Monday's fatal crash and said it was co-operating with the investigation.

A spokesman for the ride hailing service said: "Our hearts go out to the victim’s family. We are fully co-operating with local authorities in their investigation of this incident.”